Manufacture of metal wool scouring pads



Nov. 10, 1970 G. MILLS MANUFACTURE OF METAL WOOL SCOURING PADS Filed March 27, 1968 INVENTOR 650265 Mums BY ATTORNEY States atent 3,538,569 Patented Nov. 10, 1970 3,538,569 MANUFACTURE OF METAL WOOL SCOURING PADS George Mills, Salford, England, assignor to Colgate-Palmolive Company, New York, N.Y., a corporation of Delaware Filed Mar. 27, 1968, Ser. No. 716,615 Int. Cl. B2311 17/06 US. Cl. 294.5 4 Claims ABSTRACT OF THE DISCLOSURE A method of and apparatus for making metal wool scouring pads from a strip of metal wool by passing the strip on a rough surfaced conveyor through a tunnel and, by engagement of the strip with alternately spaced rough areas of the tunnel walls, rolling up the strip in successrvely changing directions. The pads may be subsequently moulded and may be impregnated before or after rolling.

This invention relates to the manufacture of scouring pads made of metal wool, more particularly but not exclusively steel wool. The pads may or may not be impregnated with a soap or other detergent composition, which may or may not contain an abrasive.

Conventionally, such pads are made by placing on a moving conveyor a strip of metal wool with the metal fibres disposed predominantly lengthwise of the strip; bringing the top of the forward end of the strip into contact with an overhead rough surface so that the front end is dragged and rolled back; continuing the rolling by contact with an overhead rough surface to form a cylindrical roll; and then compressing the roll. The compressed pad thus formed may be used as such. In the chase of impregnated pads, the impregnating composition may be applied at some suitable stage, e.g. after the roll has been formed but before it is compressed, or the impregnation and compression may be performed simultaneoulsy. The pads made in this way have considerable resistance to tearing and bending in the direction in which the metal fibres are predominantly orientated but can be easily bent and torn apart in the transverse direction.

The present invention provides a method of, and apparatus for making metal wool scouring pads which afford approximately uniform resistance to tearing and bending in all directions.

According to the present invention a method of making a metal wool scouring pad comprises placing on a moving conveyor a strip of metal wool with the metal fibres disposed predominantly lengthwise of the strip, rolling back the forward end of the moving strip by contact thereof with an overhead rough surface, and then imparting successive oblique rolling movements by contact of the edges of the moving strip with rough surfaces spaced apart on opposite sides of the conveyor.

The rolled product is not a cylindrical roll but may be roughly in the forrm of a ball or ovoid with the layers of metal fibres crossing each other in different directions. The rolled product may then be compressed.

For making pads impregnated with soap or other detergent composition, the strip may be coated or impregnated with the composition on one or both sides, or impregnated completely, or a slug or band of the composition may be laid on the strip, before the rolling operation. Alternatively, the rolled product may be impregnated with the composition after the rolling operation, for instance by dipping or by injection in a cavity or mould where the rolled product is finally shaped. For the coating or impregnation any suitable means may be employed such as dipping, spraying or application by roller, doctor blade or brush.

The invention also extends to apparatus suitable for performing the method. This apparatus may comprise a conveyor such as a belt having a rough surface to receive a strip of metal wool thereon, and a tunnel or shaft through which the conveyor passes having at its entry end an overhead rought surface disposed to engage and roll back the forward end of the strip and rough surface areas spaced apart alternately on opposite side walls of the tunnel or shaft disposed to engage the sides of the strip.

Conveniently there are two rough surface areas on each side wall of the tunnel or shaft, arranged in staggered re lationship.

The overhead rough surface may be on a flap of flexible material which is inclined downwards towards the conveyor and in the direction of motion of the latter so that the front end of the advancing metal wool strip must be engaged by this flap, but which can lift to permit the strip with the rolled back front end to pass on beneath it.

If desired the top wall of the tunnel or shaft may have one or more rough areas; preferably one adjacent the said flap to complete the first turn or so of the roll.

The cross-section of the shaft or tunnel may vary along its length, to conform approximately to the varying shape and size of the roll, in order to ensure that proper contact is made between the metal wool and, on the one hand the conveyor, and on the other hand the rough surfaces of the shaft or tunnel.

The shaft or tunnel may be capable of being raised and lowered in relation to the conveyor, to enable the apparatus to be used with strips of metal wool of different grade or thickness.

The conveyor and the flap may be formed of coarse grit emery cloth, while the rough surfaces of the shaft or tunnel may be patches of coarse grit emery cloth stuck to the walls of the shaft or tunnel.

The invention also extends to metal wool scourmg pads.

Such pads, which may be made by the method described, comprise a plurality of layers of metal wool, the fibres in each layer being disposed predominantly parallel to one another but in at least the outer layers being oblique with respect to the fibres in the adjacent layer or layers.

The invention may be performed in various Ways, and a specific embodiment and a modification thereof will now be described by the way of example with reference to the accompanying drawings, in which:

FIG. 1 is a diagrammatic isometric view of one embodiment; and

FIG. 2 is a diagrammatic isometric view of a modification.

Referring to FIG. 1, a roll 2 of steel wool strip 4 is supplied for feeding the strip to apparatus 20 embodying the invention, for producing rolled pads 6. The strip is drawn off the roll 2 and severed by a conventional cutting or tearing device 8 to produce separate lengths 12 of the strip, each of a size appropriate for making into a single pad. The apparatus 20 comprises an endless conveyor belt 22, positioned to provide for the continuous advanceof the strip lengths 12. The belt has a rough surface 24 for frictional engagement with the strip lengths 12. There is a tunnel or shaft 26 through which the strip-conveying portion of the belt passes.

The tunnel or shaft is composed of two adjustable sections 28 and 30 of approximately inverted U-shape in cross-section, which sections define the upper or top Wall 46 and the side walls 47 and 49 of the tunnel or shaft. Both sections 28 and 30 have slots 32 to permit vertical adjustment in relation to the conveyor belt. Through these slots securing means 34 are provided which engage a support frame 36 for the sections 28 and 30. The support frame has a top member 38 which constitutes the bottom wall of the tunnel or shaft and also supports the upper rim of the conveyor belt.

At the strip entry end of the tunnel or shaft there is a flap 42 of flexible material such as emery cloth which is inclined downwards towards the conveyor belt and in the direction of motion of the upper rim of the latter, providing an overhead rough surface, so that the front or leading end 14 of the advancing strip of steel wool must be engaged by the flap, but which can lift to enable the strip with its front end rolled back to pass on beneath it.

Bonded to the underside of the top wall 46 near the strip entry end of the tunnel or shaft there is a rough surface area 44 such as a strip of emery cloth.

The section 30 is provided with rough surface areas 50 spaced apart alternately on the inside of its opposite side walls. The dimensions of the section 30 are such that its opposite side walls engage the sides of the strip 12 so that as the strip proceeds through the tunnel or shaft it is progressively rolled into ball or ovoid form with the layers of metal fibres crossing each other in different directions. This occurs as a result of the successive oblique rolling movements produced by the contact of the surface of the moving rolled spiral with the spaced rough areas 59 on the side walls of the section 30.

The length and other dimensions of the tunnel or shaft can be selected as required, to con-form approximately to the varying size and shape of the rolled strip to ensure proper contact between it and the roll-forming elements of the tunnel or shaft. By vertical adjustment at the slots 32 it is possible to employ the same apparatus with strips of steel wool or varying grades and/or thicknesses.

In the modification'shown in FIG. 2 the tunnel or shaft consists of a single section 52, a horizontal wall 54 being provided near the strip inlet end to support the flap 42 and the rough surface area 44.

Upon completion of the formation of the ball or ovoid 6 of steel wool it may be subjected to the usual impregnation and moulding or compressing operations employing conventional equipment for these purposes. Alternatively, where the strip lengths 12 have been previously impregnated or coated, the final step may be merely moulding or compressing to the desired shape and size.

The method of the invention, using apparatus as described, may be performed as follows.

The roll 2 of steel wool strip 4 of the selected grade, width and thickness is set up on a suitable support and its leading end is introduced into the severing device 8 which draws off the strip 4, cutting or tearing it into the predetermined lengths 12 which pass to the apparatus 20. The leading end 14 of each strip length is applied to and engaged by the rough surface of the conveyor belt 22 and drawn thereby into the tunnel or shaft 26. As it enters the tunnel or shaft it passes under the rough surfaced flap 42 which engages and restrains the leading end 14 so that as the rest of the strip advances the leading end is turned back and as the strip continues to advance a partial roll is formed. As the diameter of this partial roll increases the flap 42 is lifted, until the strip has been advanced beyond it. The flap then returns to its original position ready to receive the next strip length, while the rolling proceeds between the rough surface 24 of the belt and the rough surface area 46 on the upper wall of the tunnel or shaft. When the still incompletely formed roll enters the second tunnel section 30 its left-hand side engages the first of the side wall rough areas 50. The direction of rolling is now changed, so that the orientation of the metal fibres in the next turn or so of the roll is oblique to the direction in the first turn or turns. Next, the right-hand side of the partial roll engages the second of the side wall rough areas, which is on the opposite side of the section 30, so the direction of rolling and the orientation of the metal fibres is changed again. These alternate changes in the rolling direction continue until the strip length has all been rolled up into a ball or ovoid 6 and is discharged from the tunnel or shaft. It is then subjected to a conventional finishing procedure, such as compression and shaping in a mould cavity, in which cavity it is also impregnated by injection with a suitable soap or other detergent composition.

In an alternative method the strip lengths 12 from the severing device 8 are passed through a coating or impregating unit 56 (see FIG. 1) before passing to the apparatus 20. In the unit 54 the strip lengths are coated or impregnated, as by spraying, with a soap or other detergent composition. The thus impregnated strip lengths 12 pass in succession to the apparatus 20 where they are rolled into ball or ovoid form in the manner already described. In this case the final operation is compression and shaping in a mould without further impregnation.

For steel wool pads, any suitable grade of steel wool may be used, for example any grade in the range 1 to 700, preferably grade 0. Long fibered steel wool is preferred because this gives the finished pads satisfactory elasticity while minimising the number of ends which could abrade users hands.

Preferred impregnating compositions have the following constitution:

Ingredient: Percent by weight Water 255O Sodium nitrite 03 Alkali metal carbonate 3-10 Polyglycol 0-6 Potassium boric acid soap (anhydrous soap and unsaponifiables) l045 Alkali metal lauric acid soap (anhydrous soap and unsaponifiables) 0.522.5 Alkali metal tallow soap (anhydrous soap and unsaponifiables) 545 Foam builder 0-6 What we claim as our invention and desire to secure by Letters Patent is:

1. Apparatus for making metal wool scouring pads, comprising: conveyor means having a rough surface to receive thereon strips of metal wool each strip having two sidesa forward end and a rearward end; tunnel means through which said conveyor means passes, said tunnel means having opposite side walls and an entry end and a discharge end; a member having a rough surface disposed overhead at said entry end to engage and roll back said forward end of each said strip; said tunnel means having rough surface areas spaced apart alternately on said Opposite side walls disposed to successively engage said sides of each of said strips, said alternately spaced apart rough surface areas being adapted to impart successive oblique reaching movements to said strips of metal wool.

2. Apparatus according to claim 1 in which said overhead member is a flap of flexible material inclined downwards towards said conveyor means and in the direction of motion of said conveyor means, said flap being disposed so that said forward end of each of said strips is engaged by said flap and being liftable to permit said strip with said forward end rolled back to pass beneath said flap.

3. Apparatus according to claim 1 in which said tunnel means has a top wall and said top wall has a rough surface area near said entry end of said tunnel means.

4. Apparatus according to claim 1, having adjusting means whereby said tunnel means can be raised and lowered relative to said conveyor means.

References Cited UNITED STATES PATENTS 1,968,310 7/1934 Peterson 29--1 JOHN F. CAMPBELL, Primary Examiner R. J. CRAIG, Assistant Examiner US. Cl. X.R. l82.4; 144-l85 

